Reverse friction-strap.



J. M. KROYER. REVERSE FRICTION STRAP.

APPLICATION FILED 0012.2, 1909.

Patented 0013.24, 1911.

Wilma/ace:

COLUMBIA PLANOGRAPH c0., WASHINGTON. D. c.

' UNITED gTATES PATENT OFFICE- JOHN M. KROYER, OF STOCKTON, CALIFORNIA, ASSIGNOR TO SAIMSON IRON WORKS, OF STOCKTON, CALIFORNIA, A CORPORATION.

REVERSE FRICTION-STRAP.

Specification of Letters Patent.

Patented Oct. 24, 1911.

Application filed October 2, 1909. Serial No. 520,719.

To all whom it may concern:

Be it lmown that I, JOHN M. KROYER, a citizen of the United States, residing at Stockton, in the county of San Joaquin and State of California, have invented certain new and useful Improvements in Reverse F fiction-Straps; and I do declare the following to be a full, clear, and exact "description of the same, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form a part of this application.

This invention relates to improvements in friction drive mechanism and particularly to the reverse drive mechanism, the object of the invention being to produce a reverse friction strap in which the strap is compressed together from both ends toward each other, thereby causing the wear and friction to be uniform throughout and leaving both the drum and the driving shaft in perfect alinement and not tending to wear out on one side as is now the case in the most commonly used form of reverse straps in which the said strap is compressed from one end only.

A further object of the invention is to produce a simple and inexpensive structure and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects I accomplish by such structure and relative arrangement of parts as will appear by a perusal of the following specification and claims.

In the drawings similar characters of reference indicate corresponding parts in the several views.

Figure 1 is a sectional view of a planetary type of transmission gearing showing the reverse strap thereon. Fig. 2 is a fragmentary view of the friction drum showing my improved reverse strap operating mechanism. Fig. 3 is a sectional view taken on a line wx of Fig. 2. Fig. 1 is a top plan view of the strap compressing means.

Referring now more particularly to the characters of reference on the drawings 1 designates the transmission drum carrying the usual type of planetary gearing 2 which, being of the usual structure, I do not describe herein in detail.

3 is the driving shaft 2111614: is the driven shaft. Being of the planetary type of transmission when the drum 1 is held stationary, the action of the shaft 3 transmitted through the gears 2 gives a reverse motion to the shaft 4 and this invention relates to the structure and means for causing the reverse friction strap 5 to grip and hold said drum stationary to permit of such reverse motion. Such strap 5 embraces the drum 1 and is split at one point as at a and at its free ends has projecting lugs 6 against which impinge dogs 7 each dog 7 having an arm.8, such arms being disposed in a parallel manner side by side and having a transverse slot 9 extending through each, the upper side of one projecting normally in a lower plane than the other as atb, and vice versa, the bottom of said second named slot projecting normally in the same relative distance above the bottom of said second named slot as at c whereby, when a wedge shaped key 10 is operated in said slots 9, it will move one arm 8 upward and the other arm 8 downward, the same relative distance (see Fig. 3) thereby causing the dogs 7 and consequently the lugs 6 to move toward each other with the same relative movement, whereby the pressure and friction will be equally distributed over the drum 1 and hence the shaft 1 and thus no unequal wear will occur on the shaft 41 as is the case with reverse straps wherein one end is fixed rigidly, and the other end alone is movable, thus giving a greater pressure of the same on one side of the drum than on the other. The key 10 may be shifted by the ordinary type of lever mechanism, hence no showing of the same is disclosed herein.

Through the dogs 7 and lugs 6 are disposed adjustment screws 11 carrying adjustment nuts 12 and 13 to properly adjust the position of the arms 8, while a spring 1 1 is interposed between the lugs 6 to return them and the strap 5 to normal loose position after having engaged the drum 1.

From the foregoing description it will be readily seen that I have produced such a reverse strap mechanism as substantially fulfils the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention.

Having thus described my invention what I claim as new and useful and desire to secure by Letters Patent is l. A device as described comprising a drum, a strap disposed around said drum and split at one point, lugs on the free ends of said strap, dogs engaging said lugs, arms on said dogs said arms lying parallel to each other and to said lugs, each arm having a slot projecting therethrough and means moving through said slots to move said arms simultaneously in opposite directions, but in a parallel manner with respect to each other.

2. A device as described comprising a drum, a strap disposed around said drum and split at one end, arms on said strap lying parallel to each other, each arm having a slot therethrough, the upper and lower dogs and said lugs, a spring disposed around the inner ends of said set screws and interposed between said lugs, an arm on each dog, such arms lying parallel with each other and parallel to said lugs, each arm having a vertical slot, the upper and lower sides of one slot lying normally in lower planes than the upper and lower sides of the other slot, and a key projecting through said slots such key having a projecting shoulder on each side, such shoulders being in different vertical planes with respect to each other as described.

In testimony whereof I afliX my signature in presence of two witnesses.

JOHN M. KROYER. Witnesses:

PERCY S. lVEBs'rER, JOSHUA B. WEBSTER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. G. 

